Permafrost monitoring network in Barentsburg as part of Eurasian Arctic high-latitude permafrost monitoring transect

The Russian Arctic scientific expedition on Spitsbergen performs permafrost observations in Barentsburg since 2016, including as a part of the Russian-German initiative to establish a Eurasian Arctic high-latitude permafrost monitoring transect covering the Spitsbergen, Franz Josef Land, Severnaya Zemlya, Novosibirskiye Islands and Wrangel Island. The permafrost monitoring network in Barentsburg includes: (1) four temperature monitoring boreholes of the Global Terrestrial Network for Permafrost with depth up to 26 m, (2) one site of the Circumpolar Active Layer Monitoring Network (CALM) for observing the dynamics of the seasonally thawed active layer equipped with an automatic meteostation, (3) a study area for repeated morphometric and temperature observations of a group of seven pingos, (4) the periodic observation and sampling of a number of groundwater springs, ice blisters and icings, and (5) the periodic ground penetrating radar and electrical survey of glaciogenic and hydrogenic taliks. The ground temperatures at a depth of zero amplitude vary from -2.2 °C to -3.56 °C. Quaternary drill core deposits, formed according to radiocarbon analysis during the period of MIS 3 - MIS 1, have a thickness up to 40 m. In the upper parts deposits are mainly represented by gravel with structureless cryostructure. The lower parts of the core sections are built by clay with streaky cryostructures. Clays are characterized by high salt content and thus freezing temperatures between -1 and -2 °C, which makes them highly sensitive to even slight ground temperature increase. The measurements of the active layer dynamics on a CALM site showed values from 1.15 to 1.60 m with an average of 1.38 m in 2017. The upper boundary of pingos ice body was observed at the depth 1.5 – 13.0 m, thus some of them are degrading or soon will start to degrade due to propagation of 0 °C isotherm to the ice.